ProjectWise Deliverables Management External Users

We are a larger firm but do have some smaller projects where the subs on these projects are small enough not to have use Bentley products before or have CONNECTION Profiles.  So we have a group that wants to try/use the PW Deliverables Management and some of the participants would be these smaller subs that have never done anything with Bentley Products.  So the question is this:  If we have these External participates, we can tell them to create a Bentley Profile but when they do they get a message saying they are not associated with an organization.  What should we tell them they should do to be able to participate in Deliverables Management of a CONNECTED Project?